A Practical Approach for Producing Hydrophobic and Elastic Aerogels by Ambient Pressure Drying

Abstract:

Hydrophobic and elastic aerogels derived from methyltrimethoxysilane (MTMS) precursor were prepared by ambient pressure drying under various processing conditions, and their morphology and physical and mechanical properties were characterised and evaluated. The results of this study demonstrated that for inherently hydrophobic gels like MTMS based gels, high temperature ageing is a practical and effective means to reduce volume shrinkage and produce low bulk density monolithic aerogels at ambient pressure, without the need of any solvent exchange and surface modification. By using this simple method, we were able to produce an aerogel with a bulk density as low as 0.064g/cm³. The results also revealed a significant difference from that previously reported in the literature.

• Periodical: Advanced Materials Research (Volumes 343-344)
• Pages: 205-211
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.343-344.205
• Online since: September 2011
• Authors: Jackie Y. Cai, Bi Xu, Li Jing Wang, Yi Cao, Niall Finn, Zai Sheng Cai
• Keywords: Aging, Ambient Pressure Drying, Hydrophobic Aerogel, Methyltrimethoxysilane, Volume Shrinkage

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